Been scouting parts for a DIY 3-way component system for my audi over the last few weeks, as i've been unhappy with my kenwood 25th anniversary 6.75's (i know, kenwood, i know, i know i know, i was an idiot)

but i digress, i'd like to keep my current 4-channel amplifier and bridge the amplifier to 2-channels, which will deliver 240w rms @ 4 ohms per door, which is more than enough, so i'm just gonna use a 3-way passive xover set

my question is regarding the resistance of speakers

if i have a 4ohm woofer, 4ohm midrange and a 6ohm tweeter, then what resistance will my amplifier see?

are the resistances combined at all? Or will my amplifier see a 4 ohm load on frequencies going to the woof, 4 ohm on frequencies going to the mid, and 6 ohms on frequencies going to the tweeter?

And if this is the case, what resistances will the amp see on in-between frequencies, that are going to two drivers (only 12db slopes)?

thanks guys, i know it's elementary, but need to make sure, and sometimes simple questions are the hardest ones to search for

Spud2388

08-13-2006, 11:13 PM

If I understand you correctly, you want to run the woofers, mids, and highs off a bridged 4 channel amp? If I'm not mistaken, you don't want to do that. The proper way to run an active 3-way setup is to have the woofers off 2 channels, the mids off 2 channels, and the highs off 2 channels, using the amps crossovers or a separate crossover to limit the frequencies to each speaker. Some poeple do a semi-active setup and have the woofers off 2 channels, and then have 2 channels going to a passive crossover, which in turn sends splits the signal to the mids and highs.

heyman421

08-13-2006, 11:20 PM

passive, not planning on running them active

just want to know how the resistances of the 3 different drivers interact at xover points

~Magick_Man~

08-13-2006, 11:24 PM

well if the passive crossover is set to use a 6 ohm tweeter and 4 ohm other drivers everything will be okay.
but if it was designed to use all 4 ohm drivers than a 6 ohm tweeter would mess up the tweeter crossover point.

~Magick_Man~

heyman421

08-13-2006, 11:48 PM

hehe, this question was hypothetical

i just want to know what my amplifier's seeing

i want to make sure i pick the right drivers for how much power they'll be getting/ not too much

i mean, does the amplifier only see the resistance of the actual speaker playing that specific frequency?